Re:Lion Air crash: Investigators say plane was 'not airworthy'
by _bear on Wednesday November 28, 2018 @08:14AM
(#18551154)
>This is the million dollar question. Why didn't the pilots turn off the system and fly in "legacy mode" like they would if they were flying the prior revision of the 737.
As a pilot, if my plane is doing something which I don't expect it to - my first thought isn't to disable auto-trim, but to consider why it's doing that. A previous crew did have the issue, and did report the problem. As a pilot, I trust that it has been fixed, so no, it wouldn't be the first thing on my mind.
Re:Lion Air crash: Investigators say plane was 'not airworthy'
by ithinkinstereo on Wednesday November 28, 2018 @08:53AM
(#18551410)
From what I understand from reading PPrune forums, pulling the circuit breaker for trim irregularities is the de facto standard operating procedure on the 737, and has been for over a decade+.
Hopefully they find the CVR and that gives us more insight into what the crew was thinking. It is odd that the pilots struggled with trim controls for ~11 minutes and didn't think to disable it.
The media has focused on the new MCAS system on the 737-Max, but I think that is somewhat irrelevant, considering that the procedures for addressing trim irregularities non-Max models are the same: pull the trim circuit breaker.
Well that's kind of a useless conclusion without the report having anything to back it up. It's really easy to pat yourself on the back and say "yup, wasn't air/road/sea-worthy" in hindsight after there's been an accident.
>Pilots tried to correct this by pointing the nose higher, until the system pushed it down again. This happened more than 20 times. It is unclear why the pilots did not employ procedures to disable the automated system.
This is the million dollar question. Why didn't the pilots turn off the system and fly in "legacy mode" like they would if they were flying the prior revision of the 737.